The Prime Minister's decision to advertise the lavish dinner enjoyed by the leaders is the quickest way of reminding everyone that we're not "all in this together".

David Cameron welcomes Barack Obama during the official arrivals for the start of the G8 Summit at the Lough Erne resort near Enniskillen in Northern Ireland. Photograph: Getty Images.

As polls regularly attest, one of the biggest obstacles to a Conservative victory at the next election is the perception that the party is both of the rich and for the rich. One recent survey found that 64 per cent believe that "the Conservative Party looks after the interests of the rich, not ordinary people", while Labour enjoys a 17-point lead over the Tories as the party most likely to treat people fairly.

So it is unclear why David Cameron thought it wise to tweet the luxury menu enjoyed by the G8 leaders last night. No one would expect the leaders to dine on gruel and water, but Cameron's decision to advertise their lavish reception, before breezily remarking, "I'll chair a discussion on tax, trade, transparency and Syria", shows a remarkable lack of tact. It reminds everyone, in just eight words, that "we're not all in this together" and provokes exactly the kind of questions he should seek to avoid: "how many food banks have you visited recently?" Neither Tony Blair, with his finely-honed political antennae, nor Gordon Brown, with his hairshirt Presbyterianism, would ever have committed such a faux pas.

Cameron's tweet is a good example of what Conservative MP Sarah Wollaston recently described to me as "a kind of blindness". Referring to the social narrowness of his inner circle, she said: "it's a kind of blindness to how this looks to other people and why it matters to other people . . . It’s not just the message, it’s the messenger. This is something that they obviously don’t see; they don’t see something that, to me, seems pretty obvious."

Similarly, Cameron, having enjoyed a fine (and taxpayer-funded?) meal, sees nothing wrong with sharing this fact with an austerity-scarred public. If the Tories are ever to win again, their next leader will need to be someone who does.